Coating to be applied onto articles such as car bodies is required to excel in coating performance such as scratch resistance, acid resistance, stain resistance and finished appearance.
Conventionally, melamine crosslinking type paint is generally used as paint for car bodies. Melamine crosslinking coating is a paint which contains hydroxyl-containing resin and melamine resin crosslinking agent, and shows high crosslinking density when cured by heating. The resulting melamine crosslinked coating excels in coating performance such as scratch resistance and finished appearance, but is subject to a problem that it is prone to be hydrolyzed by acid rain, i.e., is inferior in acid resistance.
JP Hei 6 (1994)-220397A discloses a two package type urethane crosslinking coating composition comprising hydroxyl-containing acrylic resin, hydroxyl-containing oligoester and isocyanate prepolymer. The coating film formed of this paint excels in acid resistance because urethane-crosslinked bonds are difficult to be hydrolyzed, but has a problem that its scratch resistance is insufficient.